1. Field of the Invention
The invention relates to a process for producing a film for controlling a chemotactic function. The film is composed of a thin film of a chemotactic factor substance in which the chemotactic factor substance is in a state in which it has a concentration gradient in one direction. The invention also relates to an artificial material which includes a film for controlling the chemotactic function on a substrate, and a process for producing the artificial material.
2. Description of the Related Art
Recently, it has been determined that the structure of an artificial material, in which the cell function can be controlled, contributes greatly to the formation of a biological material with a precise function for use in the study of a cell function and the like.
For a particular type of artificial material, a material is used in which a cell growth factor or a cell adhesion factor has been fixed on a substrate of glass or a high molecular substance. Research is being conducted in which cell growth and differentiation are controlled by an artificial material of this arrangement.
In order to conduct this research, an artificial material is produced on a substrate of glass or a high molecular substance in which a chemotactic factor substance, such as insulin or the like, has been fixed, and using this artificial material experiments are carried out with respect to the cell breeding process, cell differentiation, cell motion, see for example “Control of cell function by gradual fixing of the surface density of physiologically active macromolecules”, “Polymer Preprints”, Macromolecule Society Association, Sep. 20, 1999, Vol. 48, No. 10, pp. 2411 to 2412.
The following issues have become evident as a result of the recent research:
On a thin film of chemotactic factor substance, the cells move in the one direction with a higher concentration of the chemotactic factor substance by a process of determining or consuming the chemotactic factor substance.
This behavior of the cells depends on the activity of the cells themselves.
The speed of motion is higher, the greater the cell activity.
The speed of motion is lower, the less the cell activity.
It is therefore possible that a cell's activity can be confirmed by measuring the speed of motion of the cells using one of the above cell properties. However, in order to measure the speed of motion of the cells, a thin film is required in which the concentration of the chemotactic factor substance, positioned in an extremely small area, changes essentially continuously in one direction, but a process for producing a thin film with this positioning and concentration gradient is not presently known.